As Kevin Rudd, his wife Therese, their band of political advisers and a motley crew of journalists and cameramen flew in this weekend for a surprise visit, it was perhaps less dangerous than it had been at times in the past but it was dusty and nudging 45 degrees Celsius.

Mr Rudd, dressed in a pressed white shirt that seemed to remain defiantly sweat free, almost certainly knew what he was getting in to.

This was his fifth visit to Tarin Kot. He first came as prime minister just a week after he was elected in 2007.

A lot has changed in the war and in politics since then.

Now, just a month after winning the long fight to retake the leadership from Julia Gillard, Mr Rudd was back on ground.

For any prime minister, a visit to the troops is an important show of support for the soldiers and for the mission.

It's time we brought you home... when the flag of Australia is brought down for the last time a few months from now, you will have been a part of history.

Kevin Rudd

But for Mr Rudd, this visit was also a pre-campaign whistlestop designed to have maximum impact back at home.

It will play well, no doubt.

Pictures of Mr Rudd mobbed by men and women in uniform certainly will not do him any harm.

But it was also a genuine opportunity for the Prime Minister to thank the troops for a job well done.

The mission has been accomplished, he told them. Thanks to their efforts, Afghanistan was no longer a safe haven for Al Qaeda.

Australian troops had also fulfilled their promise to help train the Afghans to manage their own security.

"Your mums and dads, your brothers and sisters, your wives and husbands and partners and your kids are all enormously proud of you," he said.

"It's time we brought you home... when the flag of Australia is brought down for the last time a few months from now, you will have been a part of history."

Three quarters of the base will be dismantled by Christmas

The drawdown from Tarin Kot is now well underway.

By Christmas, three quarters of the base will have been dismantled and sent home. The rest will be gifted to the Afghan National Army.

One thousand of the 1,300 Australian troops will be brought home, with the 300 remaining to work as trainers and advisers based in Kabul and Kandahar.

There will also be an unspecified number of special forces troops committed to ensure the stability of the country as required.

The Afghan leadership has also expressed its thanks to the Australian troops.

Speaking before an official meeting with Mr Rudd, Uruzgan province governor Amir Mohammad Akhundzada said the Australian presence had helped shore up his position.

He said the Australians will leave the province a more secure place, with 200 new schools and 200 kilometres of new road.

Mr Akhundzada predicted the Afghan army could still be fighting the terrorists for another decade.

"The war on terror will not end overnight," he said.

Forty Australians and many thousands of Afghans have died in the conflict, which has become Australia's longest military engagement.

Before they left, Mr Rudd and Ms Rein laid a wreath in remembrance of those Australians soldiers who made the ultimate sacrifice.

No doubt there will be another solemn ceremony when the Australian flag is lowered for the last time here at the end of the year.

Perhaps the Australian prime minister will be here for that too. The question is will it be Kevin Rudd?

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